variable_expr.h

由matlab开发的hybrid系统的描述语言

/*
	HYSDEL
	Copyright (C) 1999-2002  Fabio D. Torrisi

	This file is part of HYSDEL.
    
	HYSDEL is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public
	License as published by the Free Software Foundation; either
	version 2 of the License, or (at your option) any later version.

	HYSDEL is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public
	License along with this library; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

	CONTACT INFORMATION
	===================
	Fabio D. Torrisi
	ETH Zentrum
	Physikstrasse. 3 ETL,
	CH-8032 Zurich
	Switzerland
	mailto:[e-mail] (preferred)
*/

#ifndef D_VARIABLE_EXPR
#define D_VARIABLE_EXPR

#ifndef STD_NS
#define STD_NS
using namespace std;
#endif

#include "Terminal_expr.h"
class Var_symbol;
class Affine_func;

/** a variable, i.e. its value is not known */
class Variable_expr : public Terminal_expr {
public:
	Variable_expr(const Var_symbol * s, const Globals * glob) :
		Terminal_expr(glob) {
			value = s;
	}

	string to_matlab() const;

	bool is_const() const { return false; }

	bool is_real() const;

	bool is_logic() const;

	/** converts a Bool variable into CNF_clause */
	CNF_clause * compute_CNF() const;

	Affine_func * compute_affine() const;

	bool is_affine() const;

	bool is_symbolic() const;

	const Var_symbol * get_value() const { return value; }

	void semantic_checks();

	bool is_number() const { return false; }

	Number * compute_number() const {
		assert(0);
		return 0;
	}

	bool is_variable_expr() const { return true; }

private:
	Expr * shallow_copy() const;

	const Var_symbol * value;

};
#endif //D_VARIABLE_EXPR